As with The Independent, the tabloid edition will sell alongside the broadsheet newspaper.
It had been reported last month that The Times was planning to wait until the new year to launch a tabloid edition, following the success The Independent has had after it launched its tabloid edition on September 30.
Robert Thomson, editor of The Times, said: "The Times is one of the oldest and most respected newspapers in the world and we are making newspaper history again as we embark on a significant change of format. The compact Times will be the same size as a tabloid, but it will be very, very different to the average tabloid, as it will bring the values and the content of the broadsheet to its new shape."
He added: "The compact Times will offer readers a dynamic and compelling read in a format that fits their lives, whether for those commuting on the Underground or for those who will sometimes want another format other than the wonderful expanse of a broadsheet. Outstanding editorial quality forms the basis of everything we do, whatever the shape, and the compact, like the broadsheet, will be informed by expertise, wit and passion."
With The Times edition nearing the printers, The Guardian and The Daily Telegraph are expected to quickly respond.
The launch will be backed by a TV advertising campaign and it is believed one of the reasons to bring the launch forward was to avoid the cost and glut of TV advertising in the pre-Christmas period.
Clive Milner, managing director of Times Newspapers, said: "The compact Times is yet another example of the willingness of TNL to invest in our products and will give our readers more choice and our advertisers more value."
Guardian Newspapers marketing director Marc Sands told Marketing recently that if The Times went tabloid, The Guardian would have to respond quickly. Telegraph Group managing director Hugo Drayton said that a tabloid was ready to go, but indicated the Telegraph might hold back to claim it was "the only serious broadsheet".
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